To better characterize the idiopathic hyperlipoproteinemia of Miniature Schnauzer dogs, the plasma lipoproteins of 20 Miniature Schnauzers (MS) and 11 dogs of other breeds (DOB) were evaluated by ultracentrifugation, electrophoresis, and biochemical tests. Seventeen M S were healthy; 3 had diabetes mellitus. Plasma from 6 of 17 healthy and all 3 diabetic M S was visibly lipemic. Lipemia was slight to marked in healthy lipemic MS, and marked in diabetic ones. All DOB had clear plasma; 8 were healthy and 3 had diabetes. All healthy lipemic MS and diabetic lipemic M S had hypertriglyceridemia associated with excess very low density lipoproteins. Chylomicronemia was present in 4 of 6 healthy lipemic M S and all 3 diabetic lipemic MS. Lipoproteins with ultracentrifugal and electrophoretic characteristics of normal low density lipoprotein were lacking in 4 of 6 healthy lipemic MS. The lipoprotein patterns of 4 of 11 healthy nonlipemic M S were characterized by mild hypertriglyceridemia associated with increased very low density lipoproteins and a lack of lipoproteins with characteristics of normal low density lipoproteins. Lipoprotein patterns of diabetic DOB closely resembled those of healthy DOB those of diabetic lipemic M S resembled those of markedly lipemic healthy lipemic MS. In conclusion, the hyperlipoproteinemia of Miniature Schnauzers is characterized by increased very low density lipoproteins with or without accompanying chylomicronemia; some affected dogs may have decreased low There is evidence that primary hyperlipoproteinemias occur in dogs, but these disorders have not been well characterized, and their etiologies have not been established."6 In one report, primary hyperlipoproteinemia was believed to be the cause of the persistent fasting lipemia of five Miniature Schnauzers. Serum from these dogs formed cream layers on refrigeration, indicating the presence of chylomicrons. Triglyceride concentrations were moderately to markedly increased, and cholesterol concentrations were moderately increased. Lipoprotein electrophoresis showed lipoproteins that stayed at the origin (expected behavior of chylomicrons), and greater amounts of beta and alpha-2 migrating lipoproteins than were seen in healthy dogs.5Several hereditary disorders that cause fasting hypertriglyceridemia occur in people, and many of these are characterized by chylomicronemia. The hyperlipoproteinemias that involve chylomicronemia are often associated with abdominal pain and/or pancreatitis, and dia- 253

Spirochetemia was diagnosed in 2 Siberian Huskies and a Rottweiler from the northwestern region of Texas between June 1999 and October 2001. Clinical findings were nonspecific; tick exposure was documented in 2 of the dogs. Hematologic abnormalities included anemia (n=2), neutrophilia (n=2, including 1 with a left shift), lymphopenia (n=3), eosinopenia (n=3), and thrombocytopenia (n=2). One anemic dog had a positive Coombs' test. In 1 dog, Western blot analysis of serum yielded multiple positive bands with B turicatae lysate, indicating the spirochetemia most likely was due to B turicatae infection. In 2 dogs, spirochetes were cultured from the blood and identified using DNA analysis as Borrelia turicatae; 1 of these dogs also was seropositive for Ehrlichia canis and B burgdorferi. In 2 cases, spirochetemia was more prominent in blood smears prepared immediately after sample collection than in smears prepared from EDTA blood. Two dogs recovered with doxycycline treatment; 1 dog declined clinically despite treatment and was euthanized. B turicatae is the agent of tick-borne (endemic) relapsing fever in humans and is distinct from B burgdorferi, the agent of Lyme disease; however, serologic cross-reactivity may occur. B turicatae is transmitted by the soft tick, Ornithodoros turicata, and infection should be considered in dogs with spirochetemia and possible exposure to the tick vector.